1. Field of the Invention
The present invention relates to a surge device for use with equipment used in air drilling a well. More specifically, the present invention is a surge device that inserts in the flow or blooie line and contains connectors for attaching two surge lines and contains a blowdown or vent line for bleeding off pressure from the well bore.
2. Description of the Related Art
During air drilling of a well, the workmen will need to break the string of drill pipe frequently to make up new connections in the drill string. Before workman can safely break the string, they must first insure that pressure has been bled off of the drill pipe so that the pressure will not blow out at them as they break the string. Also before they can safely break the string, they must insure that flammable gas is constantly removed from the well while they are making the connection so that flammable gas from the well does not flow onto the drilling platform and cause an explosion or fire as they break the string and make the connection. Currently, a blow down line and surge lines are installed in the blooie line to insure, respectively, that pressure is bled off of the drill pipe prior to the workmen breaking the pipe and that flammable gas from the well is constantly pulled out of the well via the blooie line as the workmen break the string and make the connection.
The current method of installing these surge lines and the blow down line in the blooie line is to cut at an angle one end on each of three pipes and then weld the angled cut end of each of the three pipes to openings previously cut into the side of the blooie line. When thus attached to the blooie line, one of the pipes serves as the blow down or vent line and the other two pipes serve as surge lines.
The problem with the current method of installing these pipes to the blooie line is that due to the highly abrasive nature of the material that is passing through the blooie line, the three pipes and their connection to the blooie line do not hold up well and are often the point at which abrasion causes a failure in the blooie line. This can result in downtime to fix the leak and can result leakage of flammable gas that can explode or catch on fire.
Another problem with the current method of installing the two pipes to the blooie line that will serve as the surge lines is that the openings in the blooie line to which the angled ends of the pipes are welded is an elongated oval shape. This elongated oval shape orifice does not function well to direct air in a downstream orientation within the blooie line as the air flows into the blooie line from the surge lines. It is important that the air that enters the blooie line from the surge lines is directed in a downstream orientation because when the air is thus directed, a vacuum is created in the upstream or well end of the blooie line. This vacuum is the means for removing flammable gas from the well when the workmen are breaking pipe to make up a connection in the drill string. If the surge lines are not effective in pulling a vacuum on the well, flammable gas originating in the well could travel upward through the wellhead where it could explode or ignite, resulting in disastrous injury to workmen and damage to the drilling rig.
The present invention addresses these problems by providing a surge device that is provided with flanges that allow it to be removably installed in-line on the blooie line so that if there is a failure with either the surge lines or with the blow down line, the surge device can be unbolted from the blooie line and replaced in its entirety. The ability to replace the surge device eliminates the need for special on-site pipe cutting and welding on the blooie line in the event of failure on the surge lines or blow down line and greatly reduces down time that would normally occur with the present method of installing the surge lines and blow down line directly into the blooie line.
Also, the present surge device provides for better and more reliable orientation of the surge lines relative to the blooie line, thereby insuring that the surge lines are effective in pulling a vacuum on the well sufficient to safely remove flammable gases from the well via the blooie line. Further, the present invention is provided with a reduction in the exit diameter of the surge lines where they terminate within the surge device, thereby insuring high velocity of air flowing from the surge lines into the blooie line.
Finally, the present invention is provided with a shield pipe internally that shields the surge lines and blow down line from abrasion by the materials that flow through the blooie line, thereby resulting in less chance of failure at these locations. Internal surfaces of the present invention are constructed with abrasion resistant plate to extend the useful life of the invention.